new Application "Gas blender toolkit"

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@Oleg G. I would also have a feature request. I know this is quite unusual but would make your app even more useful for me (and possibly others).
I usually blend my rebreather diluents using banked nitrox (EAN32) and high pressure Helium. Nitrox is often less than 200 bars max, while He is usually upt to 300 bar and can be boosted. My rebreather cylinders are 300 bar.
Thus, I would find very useful to have another fill order in partial pressure blending mode which would allow us to calculate exact blends when high pressure He is available available and we want to blend higher end pressures than banked nitrox allows.
This would be (O2, Topoff, He) mode in addition to present modes.

Good idea, thank you!
added new mode: (O2, Topoff, He)
 
Thanks for adding the gas density column. I would make the units g/L even if "Imperial" is toggled for the unit system. Sometimes (really, all the time :wink:) metric is better, but especially in this case since all of the recommendation are to keep gas density under 5 g/L.

The question I ask myself is how high is the relevance of the gas density when planning the dive. Whatever must be considered is the toxic and narcotic effect of the respiratory gases in depth. Is there a constellation where we stay within these limits and the gas density exceeds 6 g / l? If this constellation does not exist, does it make sense to consider gas density?
 
g/L for density even in "imperial" units :)
 

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The question I ask myself is how high is the relevance of the gas density when planning the dive. Whatever must be considered is the toxic and narcotic effect of the respiratory gases in depth. Is there a constellation where we stay within these limits and the gas density exceeds 6 g / l? If this constellation does not exist, does it make sense to consider gas density?
Yes, gas density over 5 g/L might be a more serious issue than ppO2 over 1.4. The Alert Diver article I linked above has a good discussion and shows how CO2 retention starts to spike around 5.2 g/L. For example, 32% is 5.7 g/L at its recreationally acceptable MOD of 110ft.

IMHO, gas density over 5 g/L is as important as watching the pp02. It is also the best argument for using He at recreational depths--if only He were cheaper...

Thanks so much for your continuing updates and changes!
 
A new feature added: during filling the cylinder gets warmed up. It is essential, to know the exactly pressure for deviated temperature. The "Gas blender toolkit" helps to see these deviations with help of so named Isochore of scuba tank.
 

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I frequently blend with banked nitrox, typically 40%. Looking for a mode to calculate how 40 to add to the cylinder and then topping off with air to achieve a desired nitrox mix.
 
I frequently blend with banked nitrox, typically 40%. Looking for a mode to calculate how 40 to add to the cylinder and then topping off with air to achieve a desired nitrox mix.

Start with an "unlimited" pressure in the supply tank of 40% (or the volume/pressure of your bank). Sent the pressure to what you want the final fill to be. Set the receiving tank to 21% and it's size, and slide the "existing pressure" until you get your final desired mix in the resulting tank. Subtract the pressures and you have your amounts...

Now do your fill in the opposite order....
 
Bob,
Very nice, didn't think of using the calculator in that way. Often the cylinder has remaining nitrox and I'd like to avoid draining the cylinder. So as an example I'd like start with 1500 psi of 28% and be able to calculate how much 40% add and then top off with air (21%) to have a final mix of 32% @ 3442.
 
A new feature added: during filling the cylinder gets warmed up. It is essential, to know the exactly pressure for deviated temperature. The "Gas blender toolkit" helps to see these deviations with help of so named Isochore of scuba tank.

Edited. This is great. Makes the app even better. Thank you!

How do you measure the temperatures during pp filling yourself?
 
https://www.shearwater.com/products/perdix-ai/

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